David Haye has been forced to postpone his rematch with Tony Bellew after tearing his biceps during training.
The injury-prone heavyweight, 37, has withdrawn from the match-up scheduled for December 17 at London's O2 Arena but is not considering retirement and hopes to instead fight his rival on March 24 or May 5.
"I am devastated to announce my much-anticipated rematch against Tony Bellew has been postponed until Match 24 or May 5, subject to scheduling," Haye said.
"Despite the recent injury rumours, I was in perfect condition with an incredibly strong training camp, weighing lighter than I have for more than five years, I couldn't wait to get back in the ring. I was ready to rewrite the ending of the Haye-Bellew saga."
What Haye described as a "freak accident" occurred last Thursday, and led to a procedure on Monday afternoon that he insists has been successful.
"After a freak accident during a stair conditioning session, which I've done with no incident hundreds of times, I lost my footing and slipped," he said.
"So I instinctively grabbed the banister to stop myself toppling down the stairwell, in doing so I somehow managed to damage my biceps in the process.
"I underwent a procedure to repair it; this was pretty straightforward and my doctor and physiotherapist have no doubt that not only will I make a full recovery but will be able to be back in the gym to start my arm rehabilitation in two weeks.
"I would like to apologise to Tony, his family and his training team, as well as all our fans who have been left disappointed."
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Deontay Wilder wants Anthony Joshua's management to stop "ducking" him and set up a fight for the WBC heavyweight championship.
The 32-year-old American, who is prepared to travel to Britain to defend his belt against WBA and IBF champion Joshua, has accused promoter Eddie Hearn of delaying negotiations over a bout.
Wilder told BBC Sport: "I think Eddie is ducking me more so than Joshua. If Joshua's a strong champion, a true champion, you guys in England should smoke him out, make him fight.
"You should see if he's the best. My heart says I'm the best, if I'm not I want someone to show me."
Joshua recently retained his belts by beating Carlos Takam in Cardiff and while Wilder would rather fight on home turf, he is willing to cross the Atlantic to face the Olympic gold medal winner.
"Packing out stadiums looks good but the money and Mecca of boxing is in America," Wilder added.
"But if you want to stay at home like a little girl, this king has no problem travelling to knock out the champion."
Undefeated WBC heavyweight champion Deontay Wilder has thrown down the gauntlet to Anthony Joshua after devastating Bermane Stiverne in a mandatory defence of his title.
After knocking his opponent out in a brutal first round at the Barclays Centre in Brooklyn, the US boxer called out to his British rival: "I declare war on you. Do you accept my challenge?"
There appeared to be no contest between Wilder, who is unbeaten in his professional career, and Stiverne, who was sent crashing to the canvas three times before the referee called time on Saturday's fight in the first round.
His sixth title defence, Wilder now has 39 undefeated fights and 38 KOs to his name and wants to unite the heavyweight titles.
Asked by Showtime Sports about fighting IBF and WBA champion Joshua, 28, he said: "I've been waiting on that fight for a long time now.
"I declare war upon you. Do you accept my challenge? I've been waiting for a long time. I know I'm the champion. I know I'm the best. Are you up for the test?
"A king doesn't chase the peasants. A king takes kings. I want Joshua. If he doesn't give me the fight we have other plans.
"The world wants Joshua, the world wants Wilder, I want Joshua. Joshua come and see me baby. No more dodging, no more excuses. Make the date, don't wait."
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